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    <title>练习2</title>
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        <h1>This is a heading</h1>
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          Veggies es <span class="alert">bonus vobis</span>, proinde vos postolo
          <span class="alert stop">essum magis</span> kohlrabi welsh onion daikon
          amaranth tatsoi tomatillo melon azuki bean garlic.
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        <h2 id="special">A level 2 heading</h2>
        <p>Gumbo beet greens corn soko endive gumbo gourd.</p>
        <h2>Another level 2 heading</h2>
        <p>
          <span class="alert go">Parsley shallot</span> courgette tatsoi pea
          sprouts fava bean collard greens dandelion okra wakame tomato. Dandelion
          cucumber earthnut pea peanut soko zucchini.
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